But, when you were married, the preacher said that the two of you have become “one.” You are no longer individuals but “one.” Your finances become one. You and your spouse’s incomes are “one.” Your individual bills became “one.” Your finances should be as united as you are.
One of the ways we can live as the “one” we are is to instead of thinking in terms of “me” and “mine” think in terms of “us” and “ours.” Her income is both of "yours." His income is both of "yours." After all, the two of you became "one" and your finances should reflect that. There is a lot of talk about pronouns these days, but the only pronouns couples need to concern themselves with are “us” and “ours.”